What is CVE-2026-42521?

CVE-2026-42521 is a medium-severity vulnerability in Jenkins Matrix_authorization_strategy, classified under Deserialization of Untrusted Data. CVSS score: 6.5/10. Published 2026-04-29.

How severe is CVE-2026-42521?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Deserialization in Jenkins Matrix_authorization_strategy

CVE-2026-42521

Jenkins Matrix Authorization Strategy Plugin 2.0-beta-1 through 3.2.9 (both inclusive) invokes parameterless constructors of classes specified in configuration when deserializing inheritance strategies, without restricting the classes that…

Vulnerability class: Insecure Deserialization

EPSS: 0.001 (24.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.

Affected products

Jenkins Matrix_authorization_strategy — versions 2.0
Jenkins Project Matrix Authorization Strategy Plugin — versions 2.0-beta-1

Weakness classification (CWE)

CWE-502 — Deserialization of Untrusted Data

References

Jenkins Security Advisory 2026-04-29 (vendor-advisory, Vendor Advisory)

Frequently asked questions

What is CVE-2026-42521?: CVE-2026-42521 is a medium-severity vulnerability in Jenkins Matrix_authorization_strategy, classified under Deserialization of Untrusted Data. CVSS score: 6.5/10. Published 2026-04-29.
How severe is CVE-2026-42521?: Medium severity. CVSS v3 base score is 6.5 out of 10.